Understanding determinants of tropical forests stocks and fluxes from plot to landscape levels.

热带森林占地球表面的12%，拥有一半以上的陆地多样性，并拥有超过40%的陆地碳。这些森林在全球范围内受到严重威胁，热带地区的森林砍伐占温室气体排放总量的10%左右。我的研究项目旨在加深对热带森林碳储量动态的理解。我建议扩大和提高热带森林树木多样性与碳储量和循环之间关系的预测能力。本文所要解决的具体问题是：(1)能否通过功能性状预测高碳储存物种或物种群？(2)树木多样性是否增强了碳储量和通量的稳定性？(3)树木多样性与碳库的关系如何随尺度变化？具体目标1将通过补充Sardinilla现有的功能性状数据库来解决，将补充与物候、建筑和系统发育相关的性状，并比较巴拿马、巴西和中国目标物种的功能特征与最大化C储存的地块/邻域之间的相互作用。具体目标2将利用撒丁岛的长期数据集，首次分解个体之间的相互作用在其对稳定和多样性效应的贡献中的作用。具体目标3将侧重于大树在景观层面的作用。在前期工作的基础上，本文提出样地水平上碳储量与面积的变化呈u型关系，在小空间尺度上高，在区域尺度上低。我提出的探索基金提案的影响主要体现在三个层面。通过鉴定功能性状，鉴定物种和物种组合，最大限度地提高各站点间的碳储量，提出一种提高BEF实验可预测性的方法。通过在单个树的水平上测试物种异步性和人口统计学随机性的重要性，我将巩固对所提出的统一的生物多样性和稳定性分析框架的理解。最后，通过记录物种丰富度与碳储量之间从样地到景观水平的关系变化，我将为尺度过渡理论做出贡献。这些结果将大大提高预测能力和将BEF结果扩展到景观水平的能力。这些对生态系统功能的分析与气候调节一样重要的生态系统服务相关，将对生物多样性科学的新范式做出关键贡献。

Tropical forests occupy 12% of the terrestrial surface, harbor more than half of terrestrial diversity and hold over 40% of terrestrial carbon. These forests are highly threatened globally with deforestation in the tropics accounting for ~10% of total greenhouse gas emission. My research program aims at deepening the understanding of the dynamics of tropical forests carbon stocks. I propose scaling-up and improving the predictive power of the relationship between tree diversity and C storage and cycling in tropical forests. The specific questions addressed in in this proposal are: (1) Can high C storing species or groups of species be predicted from functional traits? (2) Does tree diversity enhance the stability of C stocks and fluxes? (3) How does the relationship between tree diversity and C stocks change with scale? Specific objective 1 will be addressed by complementing Sardinilla's existing functional traits data-base will be complemented with traits related to phenology, architecture as well as phylogeny and comparing the interactions between the functional characteristics of target species and the plot/neighborhood that maximize C storage in Panama, Brazil and China. Specific objective 2 will take advantage of the long-term data set of Sardinilla to break-down for the first time the role of interactions between individuals in their contributions to stabilization and diversity effects. Specific objective 3 will focus on the role of big trees at the landscape level. Building up on earlier work, I propose that the relationship between the variance in C stocks, at the plot-level and area is U-shaped with high at small spatial scale and low at the regional scale. The impact of my proposed Discovery grant proposal will be felt at three main levels. By identifying functional traits identifying species and species combinations maximizing C storage across sites, I will propose an approach improving the predictability of BEF experiment. By testing the importance of species asynchrony and demographic stochasticity at the level of individual trees, I will solidify the understanding of the proposed unified biodiversity and stability analytical framework. Finally, by documenting changes in the relationship between species richness and C storage from plot to landscape level, I will contribute to the scale transition theory. Together these results will greatly increase the predictive power and the ability to scale-up BEF results to the landscape level. These analyses of ecosystem functioning, relevant to as important an ecosystem service as climate regulation, will make a key contribution to the new paradigm of biodiversity science.